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21.
山东日照两城镇遗址出土的浮选植物标本和植桂体表明,稻米和粟是该遗址龙山先民重要的食物来源,但由于动物骨骼保存很差,我们对他们的肉食来源所知甚少。而采用碳氮稳定同位素法探讨古人的食性和食物结构,对各种同位素含量不同的食物在当时人们食谱中的相对重要性提供了补充定量的数据。  相似文献   
22.
Carbon and nitrogen stable isotope values were measured from bone collagen extracted from archaeological Nubian human (n = 54) and faunal (n = 61) populations from the site of Kerma, Sudan. Collagen suitable for isotopic analysis was extracted from 22 faunal and 48 human samples from the Eastern cemetery site, dated to the Middle Kerma (c. 2050–1750 BC) and Classic Kerma (c. 1750–1500 BC) periods respectively. The isotopic data indicate that the human dietary regimen included a mix of C3 and C4 plant-derived components, with a larger C4 component than previously reported in archaeological Egyptian Nile Valley populations. Elevated δ15N values are attributed to consumption of dietary resources from a 15N-enriched terrestrial ecosystem. The faunal isotope data also indicate the consumption of C3 and C4 plants. The large range of δ13C values measured in both the human and faunal samples supports previous work suggesting that a significant portion of the populations buried at Kerma may have originated elsewhere, further confirming the Nile Valley as a major corridor for population movement in the region.  相似文献   
23.
Optically stimulated luminescence (OSL) measurements are reported for single grains of quartz from deposits within Sibudu rock shelter. Such measurements enable rejection of unrepresentative grains and application of the finite mixture and central age models to obtain the most reliable age estimates. Three types of single-grain equivalent dose (De) distributions were observed: one sample represented a single dose population, three samples indicated mixing between Iron Age (IA) and Middle Stone Age (MSA) deposits, and 10 samples (in addition to the three mixed samples) showed scattered distributions. The latter type resulted from differences in the beta dose received by individual grains. For these samples, the beta doses were modelled and adjusted accordingly. Ages for the 14 samples collected from MSA deposits post-dating the Howiesons Poort (HP) resulted in three age clusters, which are stratigraphically consistent with the three informally named cultural phases at Sibudu: namely, the post-HP, late MSA and final MSA. Weighted mean ages of 58.5 ± 1.4 ka, 47.7 ± 1.4 ka and 38.6 ± 1.9 ka were calculated for these phases, respectively. The three phases were separated by two occupational hiatuses with durations of 10.8 ± 1.3 ka and 9.1 ± 3.6 ka. We hypothesise that the punctuated presence of humans at Sibudu was determined by large-scale fluctuations in climate during oxygen isotope stage (OIS) 3, which resulted in alternating wet and dry periods. Phases of occupation correspond to wet periods when fresh water was available in the Tongati River, whereas intervals of site abandonment correspond to dry periods when people were forced to migrate in search of a reliable source of fresh water. Where people migrated to, remains unresolved.  相似文献   
24.
Isotopic analysis of skeletons excavated during the 1950s has confirmed that they are the remains of shipwreck victims: slaves on board the Portuguese slaving brig Pacquet Real when it sank on 18 May 1818. Twenty-five slaves drowned and the remaining 133 became Prize Negroes at the Cape. The isotopic signatures are consistent with values expected for people living in an African village eating a terrestrially based diet. Analyses of different skeletal elements, i.e., teeth, long bone, and rib, are shown to be a valuable tool in tracing change or consistency in diet during a person's life, because different skeletal elements form at different stages of life and, subsequently, remodel at different rates. A comparison of isotope ratios from different skeletal elements indicates a change in diet in all these individuals, probably coincident with their enslavement. Variation between individuals in the isotopic composition of diets eaten early in life is sufficiently large to deduce heterogeneous origins for the group.  相似文献   
25.
The Krafla geothermal system is located in Iceland's northeastern neovolcanic zone, within the Krafla central volcanic complex. Geothermal fluids are superheated steam closest to the magma heat source, two‐phase at higher depths, and sub‐boiling at the shallowest depths. Hydrogen isotope ratios of geothermal fluids range from ?87‰, equivalent to local meteoric water, to ?94‰. These fluids are enriched in 18O relative to the global meteoric line by +0.5–3.2‰. Calculated vapor fractions of the fluids are 0.0–0.5 wt% (~0–16% by volume) in the northwestern portion of the geothermal system and increase towards the southeast, up to 5.4 wt% (~57% by volume). Hydrothermal epidote sampled from 900 to 2500 m depth has δD values from ?127 to ?108‰, and δ18O from ?13.0 to ?9.6‰. Fluids in equilibrium with epidote have isotope compositions similar to those calculated for the vapor phase of two‐phase aquifer fluids. We interpret the large range in δDEPIDOTE and δ18OEPIDOTE across the system and within individual wells (up to 7‰ and 3.3‰, respectively) to result from variable mixing of shallow sub‐boiling groundwater with condensates of vapor rising from a deeper two‐phase reservoir. The data suggest that meteoric waters derived from a single source in the northwest are separated into the shallow sub‐boiling reservoir, and deeper two‐phase reservoir. Interaction between these reservoirs occurs by channelized vertical flow of vapor along fractures, and input of magmatic volatiles further alters fluid chemistry in some wells. Isotopic compositions of hydrothermal epidote reflect local equilibrium with fluids formed by mixtures of shallow water, deep vapor condensates, and magmatic volatiles, whose ionic strength is subsequently derived from dissolution of basalt host rock. This study illustrates the benefits of combining phase segregation effects in two‐phase systems during analysis of wellhead fluid data with stable isotope values of hydrous alteration minerals when evaluating the complex hydrogeology of volcano‐hosted geothermal systems.  相似文献   
26.
The presence of the osseous remains of at least four mules in a garbage dump at the Roman fort of Biriciana near the town of Weißenburg, Upper Bavaria, dating to c. 160 AD, raised the question as to whether mule breeding was already performed to the north of the Alps during the Middle Roman Empire, or whether these animals still had to be imported from the Mediterranean. Serial analyses of the dental enamel and dentine of a lower fourth premolar and the surrounding alveolar bone of a mandible of a mule in terms of stable strontium isotopic ratios of the apatite, and stable carbon and oxygen isotope ratios of the structural carbonate, were carried out to test whether this individual moved long distances during its lifetime. Since isotopic ratios obtained by serial analysis can be correlated with consecutive ontogenetic stages, it can be assumed that this particular individual experienced significant changes in terms of diet and environmental parameters after its eighth year of life. These changes included a period of residence in a region of high altitude, most likely the Alps considering the location of the Roman fort where the mule was found. The isotopic data obtained do not contradict the assumption that this animal was bred and raised in northern Italy, to frequent later in its adult life the Alps and finally perish at Biriciana/Weißenburg. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
27.
This paper presents and tests a model designed to investigate how off-site herd management developed in settled pre-historic societies. The model is constructed from data collected from traditionally raised local sheep, acting as an interpretive link to published data. The modern comparator was small, but plausible results allow modelling of the archaeological data to be explored. Birth seasonality and herding location are identified through modelled patterns in oxygen isotope data in tooth enamel, and diet just before death by microwear in the same tooth. In combination, these allow aspects of seasonal management of breeding, fallow and slaughter herd sections to be interpreted. Novel practices are discussed in comparison local wild sheep ethology. The case study is Neolithic Çatalhöyük (7400–6200 cal BC) in central Anatolia. Its location provided the opportunity for different parts of the landscape to be used for herding, although choice might have been socially constrained. Data are taken from 72 specimens; the results suggest settlement-wide preference for a suite of practices that kept herds within a day of the settlement and that maintained breeding cycle synchrony with optimal resource availability. Chronological analysis suggests birth season manipulation was tried but rejected, whilst hay or cereal fodder was introduced and became increasingly important. It is argued that herding was probably on dedicated pasture on the arable fringes rather than in closer integration on ‘garden plots’, as there is no evidence of field-edge weed diets and little evidence of adjusting the birth season to accommodate the crop cycle.  相似文献   
28.
Organic fertilizers have the capacity to alter the nitrogen isotopic composition of plants. Camelid dung and seabird guano are two potentially important fertilizers in the agricultural systems of western South America, particularly Peru and Chile. This paper presents isotopic data (δ13C and δ15N) from field grown plants (maize, Zea mays) fertilized with the following four treatments: CO (control, no fertilizer applied), AS (ammonium sulfate, a chemical fertilizer), DU (camelid dung), and SG (seabird guano). Plants were grown in experimental plots in the Virú Valley, northern Peru. Plants fertilized with the chemical fertilizer presented very similar isotopic compositions compared to the control. Conversely, the camelid dung fertilized plants were characterized by higher δ15N values compared to the control plants (by 1.8 to 4.2‰ depending on the plant part). The seabird guano fertilized plants were greatly enriched in 15N in comparison to the control plants (by 11.3 to 20.0‰). The results of this study have important implications for the reconstruction of human diet using isotopic data derived from bone collagen and related tissues, particularly in the prehispanic Andes, but also in Europe and North America during the 19th century, when Peruvian seabird guano was used extensively. Specifically, the interpretation of the relative contributions of plant and animal protein to the diet on the basis of bulk isotopic compositions of bone collagen (or similar tissues) may be confounded by camelid dung fertilization if the carbon isotopic compositions of the two sources are similar. Likewise, the interpretation of the relative contributions of maize and marine protein may be confounded by seabird guano fertilization.  相似文献   
29.
Foraging ranges, migrations, and travel among Middle Holocene hunter–gatherers in the Baikal region of Siberia are examined based on carbon and nitrogen stable isotope signatures obtained from 350 human and 203 faunal bone samples. The human materials represent Early Neolithic (8000–6800 cal BP), Late Neolithic (6000–5000 cal BP), and Early Bronze Age periods (∼5000–4000 cal BP) and come from the following four smaller areas of the broader region: the Angara and upper Lena valleys, Little Sea of Baikal’s northwest coast, and southwest Baikal. Forager diets from each area occupy their own distinct position within the stable isotope spectrum. This suggests that foraging ranges were not as large as expected given the distances involved and the lack of geographic obstacles between the micro-regions. All examined individuals followed a similar subsistence strategy: harvesting game and local fishes, and on Lake Baikal also the seal, and to a more limited extent, plant foods. Although well established in their home areas, exchange networks with the other micro-regions appear asymmetrical both in time and direction: more travel and contacts between some micro-regions and less between others. The Angara valley seems to be the only area with the possibility of a temporal change in the foraging strategy from more fishing during the Early Neolithic to more ungulate hunting during the Late Neolithic–Early Bronze Age. However, the shift in stable isotope values suggesting this change can be viewed also as evidence of climate change affecting primary productivity of the Baikal–Angara freshwater system.  相似文献   
30.
This paper presents the results of new stable isotopes (carbon and nitrogen) analysis of human, faunal and fish remains from thirteen cemeteries from the Middle and Lower Dnieper Basin, Ukraine. The results are integrated with earlier analyses, undertaken solely on human samples, in order to provide a comprehensive overview of subsistence across the Upper Palaeolithic through to Eneolithic periods in this region. This is the first time that a combined sample of human, faunal and fish remains has been studied in order to interpret subsistence strategies across these periods in Ukraine. The total dataset comprises 113 samples of human, faunal and fish remains, 59 of which include new analyses of faunal and fish remains that have not previously been made available for study (Table 1). The analysis of the faunal and fish remains allows for a consideration of trophic levels which indicates that the consumption of freshwater fish occurs from the Epipalaeolithic period onwards. Whilst the majority of the cemeteries and the individuals therein cluster in relatively tight groups, there is a significant offset between the human and faunal samples due to the consumption of freshwater resources. The fish samples analysed in the study appear to exhibit a relatively random distribution when compared to the other samples analysed. In general, freshwater resources remain significant through until the end of the Neolithic period and into the Eneolithic period at the sites investigated.  相似文献   
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